So here's my attempt at reviewing this. I also hope to find some sort of closure for my disappointment and maybe if I write it all down, then perhaps I'll finally be able to move on and leave this piece of cinematic history behind me (bit of dramatising is in order lol).

Where to start?
The opening sequence predicted so much goodness. Beautiful scenery shots of Iceland, thunderous waterfalls, a low vibration from an epic ship floating in the air. No words. The setting was great.
Then this beefed up character appears. Xerxes on steroids if you will.
They looked kind of cool, but in the end, was it not just a human on steroids? Fair enough, it drinks some goo and dissolves into the water.
And this is supposed to be how life (or even more preposterous, only human life) was formed on Earth? Let's leave that in the middle, within the realm of sci-fi it's acceptable to question 300 years of Darwinism, but personally I think this was a first uninspired choice.

Then there's some 3D masturbation, sure it put a smile on my face but honestly, in the back of my head I already knew I wasn't going to like this.
In what feels like 5 minutes later, after a pretty cool scene involving David spending his days on the ship (bit of an obvious wink to 'a Space Odyssey' if you ask me), we are ready to arrive on LV-223.
The premise for going there, a bunch of ancient drawings pointing at a Planet with a life supporting moon, seemed plausible at first. In hindsight, this is of course utterly ridiculous. Why would Aliens leave us a map with their top-secret chemical weapons lab, a lab they are apparently using to come and destroy us. X marks the spot. Then we are simply told only two characters know the details of this mission....wow? Ok...let's let that one slide as well. I mean, they have to build character at some point right, what better way than a speech?

After a weak attempt at character building, we are now on the planet where everything starts to become painful to watch. Characters make the most weird decisions: Biologist stroking dangerous looking space-cobra's, geologists with no interest in rocks, getting lost even with radio communication and probes. Deciding to sleep in the same place they ran away from because it is too scary. An archaeologist is suddenly a medical expert, examining an Alien head and performing an abortion in some weird Male-only machine that has a grappling hook like some carnival machine. The characters act completely random, ignoring all protocols. They perform actions so that something cool can happen, but all logic has forsaken the movie by now. One drip of goo makes an alien snake, the other makes a contortionist zombie. It's all too random.

Mind you, in Alien(s) too, some characters made weird decisions, but at least they were presented in a way that actually might seem plausible, or there was so much tension and mystery that you just didn't have the time to question it all, not this time though.

All sorts of slightly horrible things happen (but no gore though) to the people around them, but much like the viewer, they don't seem to care much. Even when loved ones are dieying, nobody gives a flying fuck about anything. Perhaps they were all on sedatives? How can Noomy and David still act like nothing has happened? He killed his boyfriend and impregnated here with a ridiculously sized creature (that could never fit inside her cute tiny body). I won't even begin to list all the obvious plot-holes, movie mistakes and inconsistencies, you can find some on the regular board in the Prometheus topic.
Then there's old Guy Pierce, seriously? Why? I can't understand it.
Also, the scene were David 'toys' with a flute and synthesizer and a fart cushion to control the Alien space ship...honestly? Ok I guess that's down to personal taste.
Then there is the cliché ending, entirely set up for a sequel to roll on. They could have redeemed themselves here. A beautiful scenery, one person alive and an android...they could really have let them die beautiful and let David be the star at the end as well, because it is the only character that's worthwhile, without even being original (he's just another psycho android in the end). I very much like Noomi and I would like to cuddle her much like everyone here, but her lead role and performance here are thin.

And what about the score: it is of a docile epic nature. I found it completely unfitting for a thriller. In the opening scene it sort of worked, but during the rest of the movie, the music adds nothing to the concept, if anything it detracts from it by killinh what little tension build-up there is.

But the best thing is, I am willing to forget all of the above mistakes and call it an average summer blockbuster to be seen with a bag of popcorn in hand, another hollywood cash-in. But no, they had to fuck with Alien(s). And I suppose this is a very personal part of the review, but it lies at the essence of why this movie ruined sci-fi for me.

This is not a stand-alone film, there's too many references to Alien(s) for that, even besides the Space Jockey, facehuggers and the proto-xenomorph at the end. There's scenes based on Aliens (the car driving over the contortionist zombie for example), there's text liens copied from Aliens. So the contamination had already begun. But the worst part of all of this:

By turning the xenomorphs into some random science project developed by humans, yes in the end the Space Jockey's are just that, humans, they have completely destroyed any sort of scariness, fear, profound terror that I had connected with their species when watching the first three movies.
In Alien(s), they were presented as something completely Alien, who's motives we couldn't understand: who killed, period. And who didn't live like most of the parasites on Earth, simply killing their hosts in a terrifying way. It truly instilled that fear of the unknown: something incomprehensible and truly ALIEN.
Now they might as well be German Shepard's bred by the Nazi's to kill jews or something. And the Space Jockey's think act and react exactly like humans, they have the same emotions and same shortcomings, hell with 100% matching DNA, they are humans. That epic figure sitting in his mysterious chair, that seemed untouchable, yet still got killed by the Alien bursting out of his chest, he too has been completely humanised: there is no more Alien factor in this. This entire movie could have been played out on Earth in a different contemporary context involving a science project gone wrong.

And they have tried to justify their plot-selection by adding the "Prometheus" myth to the story. It's just a disguise. The religious subplot isn't worked out at all, it just adds to the confusion and is really a thin vale to keep people from thinking too much about the hideous script. They've added some references for fanboys to drool over: the birth of Christ, who is God, what is Creation...I call bullshit, but I'm not a very religious person I suppose.
And finally, take into account the various trailers, trailers of trailers and the entire marketing machine surrounding it. Oh boy, I'm ashamed in their stead.

Maybe it's because Scott has grown old? Maybe he simply has dried out? Or did the writers influence him too much? Or was money an issue? Seeing as Fox is behind it, it could be. At any rate, declare the franchise dead: heralded as the movie that would save Sci-fi in the new decade, it is perhaps the final nail on its coffin.